The French and Indian War (1754–1763) was a turning point in the relationship between American colonists and the British government because the war

because the war left Britain in war debt  so the British government decides to tax the american colonies which infuriated the colonist  

2018 means 2018 ce or common era

there have been other eras too including bce, which included way more years.

the answer to your question is a. the salt plains

in 1811, he led an expedition, known as the george c. sibley expedition, to improve relations with the pawnee and kansa tribes, and also to locate the rumored jefferson's salt mountain